I just purchased an Asus 1005PE which led me to this thread. I have a problem which probably is much simpler than this. I have an MSI Wind nettop configured as a server. It needs to be installed 'headlessly'.
The BIOS does not allow a USB drive to be the priority boot device. It does, however, have a Compact Flash slot which can be set as the first boot device.
What I would like to have is a 'booter' that runs on the Compact Flash device that scans the usb ports, if it finds a usb drive mounted with a specific label, it will launch it resulting in initial installation of the server software to the hard drive. If it does not find that usb drive, it will boot normally from the hard drive. The key is that this must be non-interacive since there will be no keyboard or monitor available. Once the server software is installed or the system booted from hardrive, it will be administered via ssh.